Sensitization effect.

1. Approximately 15% of males were sensitized by transfusions before their first grafts. About 40% of females were sensitized by pregnancies and transfusions. Following graft rejection about 60% of males and females were sensitized. 2. The one-year graft survival of nonsensitized and sensitized patients differed by 4 to 7% in first, second, and third transplants. The difference developed very early and even on the first day after transplantation. 3. Patients with a high peak level of antibody tended to have lower graft survival, particularly in regrafted patients. If the peak level of antibody was under 50% panel reactive antibody, graft survival was the same as in patients who never had preformed cytotoxins. 4. Parous women without transfusions and no preformed antibodies had a 49% one-year graft survival with no transfusions and 71% with transfusions. Similar findings were noted in regrafted parous women and those with preformed antibodies. Thus, pregnancy exerted a deleterious effect which was reversed by transfusions. 5. Between the best and worst HLA-A,B,DR match there was a 19% difference in one-year graft survival for nonsensitized patients, and a 26% difference in patients sensitized to more than 50% of the panel. A similar difference was noted in regrafted patients for sensitized and highly sensitized patients. 6. Transfusions had a greater effect on the outcome of transplantation than the state of sensitization. First cadaver donor patients without transfusions and without antibodies had a one-year graft survival of 57% whereas patients with more than 50% panel reactive antibodies had graft survival of 59 to 71%.(ABSTRACT TRUNCATED AT 250 WORDS)